DOM绑定事件的三种方式

function handleName() {
    alert('执行了html绑定的方法')
}

	<button οnclick="alert('111')" type='button'></button>
	<button οnclick="myClick()"></button>

elementObj.onXxx = function(){}
elementObj.οnclick=function() {
    alert('111')
}

elementObj.addEleventListener(type, handele, useCapture)  // useCapture是事件流，是否捕获

elementObj.attachEvent(type, handle)

	function addEvent(obj, type, handle) {
		try {
			obj.addEventListener(type, handle, false);
		} catch(e) {
			try {
				obj.attach('on' + type, handle);
			} catch(e) {
				obj['on' + type] = handle;
			}
		} 
	}